MARTINEZ (CBS SF) – A Contra Costa judge sentenced three San Francisco gang members Monday to multiple life sentences in prison for the murder of a man and woman in 2012.

Sheldon Silas, 28, Reginald Whitley, 35, and Lamar Michaels, 29, were convicted of murdering Christopher Zinn, 24, and his girlfriend Brienna Dow, 21, in October of 2012 after their bodies were discovered on Buchanan Road in unincorporated Antioch.

READ MORE: Unique Twist To Pandemic Shutdown Of Long-Establish Santa Clara Restaurant

Prosecutor Melissa Smith said Zinn had been a friend of the three defendants, but was targeted after he allegedly stole guns from a Hunter’s Point street gang of which Silas, Whitely and Michaels were members.

Prosecutors said Dow was killed because the defendants didn’t want her to testify against them.

Superior Court Judge Clare Maiers sentenced Silas, Whitley and Michaels to life without the possibility of parole and gave additional sentences ranging from 55 to 77 years in state prison.

A fourth defendant, Linda Chaney, 41, was sentenced to 11 years in a state prison after presenting a false ID card to jail guards when she visited Whitley, her boyfriend, in jail to sneak out paperwork revealing the name of a police informant.

READ MORE: SF Restaurant Apologizes for Denying Service to Armed, On-Duty Police Officers

Chaney, who wasn’t allowed to visit with jail inmates because of a previous felony conviction, also had a metal implant inserted into her back and accused jail guards of racism if they would search her after her implant set off metal detectors, according to prosecutors.

She stuck a cellphone to the implant and snuck it into the jail.

Additionally, Chaney and another woman confronted the witness, showing them the paperwork had been released. The witness was later relocated and taken to court with a police guard where he testified during the defendants’ trial.

Although Chaney received 11 years, she will get three years credit for time served.

MORE NEWS: International Travelers Brace For New COVID Testing Requirement

© Copyright 2017 by CBS San Francisco and Bay City News Service. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.